Apparatus for developing films



I May 24, 1932- M J. W. SMITH APPARATUS FOR DEVELOPING FILMS Filed Now/.6, 1930 INVENTOR. J0 n h esl y 5m 1' UL ATTORNEYS.

Patented May 24, I932 UNITED-STATES PATENT" orrics J'OHIT WESLEY SMITH, ONPHILADELPHIA, PENNSYLVANIA, ASSIGNOR I'O AERO SEBV-a ICE CORPORATION, OF PHILADELPHIA, PENNSYLVANIA, A OORPORATION OF DELA- Arr'rus ron nsvsrorme mus Application filed November 6, 1930.- Serial in; 493,727.

My invention relates to apparatus for developing roll films of relatively large size, such as are ordinarily employed, for example, inaerial photography, aerial map-making and the like, and is especially adapted to facilitate the developing of such films in the hold, that is, where a permanent and'well equipped developing laboratory is not available, although my invention may also be used to advantage for likepurposes in such laboratories.

In development of roll films of the ordinary sizes employed in hand cameras, and the like, it has heretofore been the practice to wind the film, together with a suitable spacer or apron, upon a spindle immersed in a bath of the developingfluid, but so far as I am aware no satisfactory means'has heretofore been devised for developing roll films of the sizes usually em loyed in aerial work,

for example, a roll of 1m approximately 9" .wide and 75 long. a

- In film rolls of this class it is often highly desirable that development thereof be accomplished without cutting the film, for example 11y ortable naturef,

in order to avoid confusion in determining.

the subject of any particular ex osure, and for other reasons, but the forms 0 apparatus heretofore employed for the development thereof frequently cannot be operated satis factorily without such cutting.

A principal object of my invention there fore, is to provide means whereby roll films of large 'SIZBS may readily be developed as a sing e unit.

A further object of my invention is to provide a novel form of apparatus for so eveloping such of compact and readadapted to he employed in old work, as, or example, by an army in campaign, and which does not require a fully equipped laboratory to permit the satisfactory accomplishment of its intended functions.

. provide apparatus of the class described A still further object of my invention is to adapted to pern'n't maximum exposure of the film to the action of the hath employed in the developing process'withont requiring the use ofa large "It tank orthe like, or thet the tank I also provide end, the strip a large portion of the film be unwound from its retaining roll at any time.

Qther purposes, objects and advantages of my invention will be hereinafter more specifically mentioned or will appear from the following particular description of a preferred embodiment thereof, in which reference will be had to the accompanying drawmgs. a

In the said drawings, Fig. 1 is atop plan view of my invention, showing a roll of film in position for development therein and Fig.- 2 is a side elevationof the same, in which a portion of the tank is broken away for the sake of clearness. In both figures like characters of reference are used to designate the same parts.

Referring now more particularly to the ment of m invention is shown, I provide a tank 1, which may desirably be made of sheet Monel metal or other sheet metal suitably resistant to the developing baths, and adapted to contain the latter. Elf desired, a plurality of such tanks of difierent sizes andadapted to nest together maybe provided, thus permitting a separate tank to be used for each bath employed in the developing process.

Adapted to beremovahly disposed within a cage preferably formed of metal straps 2 and 3 respectively defining rectan ice and disposed normal to and centrally 0 each other,.thus forming in efiect a cross when viewed in plan, the requisite joints heing made "therein by rivets, spot weldin or thezlike, thus to us a rigid cage 0 light weiht. 7

Supported wi an: the cae, and t'atable therein, are two iii m cylinders 4' loosely journaled in the strap 3 on suitable vertical spindles 5 at the topiand bottom.

Crank ,arms'o may he secured to the upper spindles to permit manual rotation thereof,

and thus of the'cylinders. At the bottom of strip 9 is held in place by a hangover, tongue 10 at its a}. l axially of the-cyL inder adjacent its surface and being slightriphery of the cylinder being slightly flattened as at 12 to permit the end 0 the strip 9 to be sprung slightly inwardly to allow the catch to'be readlly slipped thereover. A s clearly shown in the drawings, the strip 91s adapted to clamp the end of a roll of film 13 against the cylinder and thereby secure the film to the latter.

In developing a roll of film with the aid of my invention the cage is first lifted from the tank and one end of the film then secured to one of the cylinders, for example 4, by passing it under the strip 9, the latter then being locked by the catch 11. The film is then wound onto the c linder by means of the adjacent crank, pre erably with the emulsion or 7 sensitized surface on the outside, so that the film then rests on its edge, and is provided with vertical support by the flange 8.

After the entire strip of film has been wound on the cylinder 4, the free or rear end thereof is secured to the other cylinder 4',

and the cage, bearing the cylinders and the film, is then introduced into the tank containing the developing bath; The cylinder l'v to which the free end of the film has been secured is then rotated by means of its crank so as to wind the film upon said'cylinder and thus the entire surface of the film isprogressively exposed to the bath as it passes from one cylinder to the other.

Furthermore, due to the ease with which the cylinders rotate, the film is not wound claims. I

tightly thereon -and thus a relatively large quantlty of the liquid of the bath is retained the film which is consequentl continually exposed to the action of the bat even after it is rolled up on the cylinder onto which it is being wound.

As is well understood in the art of developing films, it is desirable to pass the film through each bath several times, and this may be readily accomplished with my invention.

by windin the film back and forth between the cylin ers. The passage of the film through the bath and the rotation of the cylinders are thus efi'ective to maintain adequate circulation of the bath, and additionally, by arranging the film so that the emulsion is on the outside of the roll, a maximum exposure thereofto the main body of the bath is attained. Thus, assuming that the cylinders are each 4" in diameter, approximately one lineal foot of the film is exposed to the bath on the outside of each roll, and as cylinders of this size may conveniently be arranged with their centers approximately 8" apart, at least that much of the film is always exposed to the bath in its passage from one cylinder to the between adjacent convolutions' of other; thus, in apparatus of the proportions above mentioned some 2 8" of the film, measured lineally thereof, is always exposed f to the main body of the bath, while due to the inclusion of a thin layer of the bath between the convolutions of the film on the respective cylinders, all the remaining portion of the film is also being subjected to the action thereof, the vertical support provided the frequently occurs in developing by means of apparatus in which the film is wound on a spindle whose axis of rotation is arranged.

horizontally or which is incapable of very free rotation.

It is apparent that the cage, carrying the cylinders and the film, may be readily removed from the developing. bath when the development is complete or when otherwise desired and that rinsing and fixing of the film may be readily effected in the same manner as above described, either in the same tank,

after changing ofthe bath, or in other tanks containing respectively the water, fixing bath or other liquid.

While I have herein described a preferred embodiment of my invention with some particularity, it will nevertheless be understood that I, do not thereby desire or intend to limit or confine myself thereto, as changes and modifications may be made in the mode of construction'and the form and relationship of the several elements thereof, if desired, without departing from the spirit and scope of the invention as defined in the appended Having thus described my invention, I claim and desire to protect by LettersiPatent of the United States:

1. Apparatus for developing roll films comprlsing a pair of vertically disposed cylinders, a cage adapted to rotatably support said cylinders in spaced relation, a radial flange formed on each cylinder and adapted to receive and support one edge of a rollof film when wound on the cylinder, and means carried by each cylinder operable to removably secure one end of said film thereto.

2. Ihe combination with a film processing tank adapted to contain a fluid bath, of means operable to support a roll of'film on a vertical axis therein, and means operable to continuously'withdraw a strip of film from said roll and to wind, said film into another roll having a layer 'of said fluid bath uniformly included between respectively adjacent convolutions ofsaid second roll.

3. The combination with a film processing tank, of a pair of vertically disposed cylinders rotatably supported therein and each adapted to receive a roll of film, a flange carried by each of said cylinders adapted to ascents support the film received by such cylinder,

and means operative to secure oneend of said film to each of said cylinders.

4. The combination with a film processing tank, of a pair of cylinders rotatably supported therein and each adapted to receive a roll of film, a flange carried by each of said cylinders adapted to support the film received by such cylinder, a locking strip secured at one end to said flange and extending axially of the cylinder adjacent its surface, and means adjacent the other end of, the cylinder adapted for engagement over the other end of said strip.

5. Roll film developing apparatus comprising atank of greater depth than the width of the film to be developed, a pair of similar cylinders each provided with a peripheral flange adjacent one end of greater width than the thiclmess of the film when wound on the cylinder, an open cage adapted for insertion in the tank and operative to rotatably support the cylinders in spaced relation with their axes extending verticall manually 0perable means for independent y rotating each cylinder in the cage, and means comprising a locking strip extending axially adjacent the surface of each cylinder and a catch for releasably holding one end thereof, operable.

to secure an, end of the film to the cylinder,

In witness whereof, I have hereunto set my hand this 5th day of November, 1930.

JOHN WESLEY SMITH. 

